Are you talking about the solenoid on the transmission? Its connected to the manifold vacuum not directly to dist. I cant seem to find a wire schematic to show this wiring layout either? I don't know?
edit:
Ok, found some details in the original "10-30 Chevrolet Truck Service Manual", kind of hard to make out the wires and routing. I think I have some snipped wires I need to trace back?